The present invention relates generally to dental tools and more particularly to an assembly for a holder for a reciprocating tool particularly useful for filing operations performed in the practice of dentistry. The invention further relates to such a filing tool which is held in the chamber of the tool holder which receives the tool shaft and which includes a clamping device whereby at least one clamping element is pressed laterall against the tool shaft by means of the inner conical surface of a clamping nut.
In a known tool holder assembly of this type used in the practice of dentistry, a conical clamping shaft is arranged in a correspondingly shaped chamber of the tool holder in a manner to be displaced within the tool holder by means of a screw cap. In the operations of such a device, the shaft of the tool which is introduced into the tool holder from the front thereof, is rigidly connected with the tool holder by a clamping effect. However, the disadvantage of such a known arrangement involves the fact that the clamping path of the conical clamping chuck is quite short so that only tools having a certain shaft diameter maybe clamped therein.
It has been found desirable to provide a holder assembly which is capable of having inserted therein so called handfiling tools. However, a problem arises in that handles of various filing tools having different diameters and different lengths. One approach has involved the suggestion of inserting the handles of such filing tools within a tool holder chamber and to brace the tools in a length-wise manner. By utilizing corresponding conical designs for the chamber bottom and for the clamping element, the tool handle may be centered in place. However, such a tool handle involves the disadvantage that only handles having substantially equivalent lengths and outer configurations may be clamped in the same tool holder and it therefore becomes necessary to utilize intermediate pieces in order to adapt the tool holder to a different tool length.
The present invention is intended to overcome the disadvantages of known tool holders for reciprocating dental filing tools and to provide a design whereby the tool holder is capable of clamping all types of conventional handles of hand filing tools. This is achieved by virtue of the particular clamping mechanism of the present invention which enables the application of a radial clamping force to the tool holder in order to properly hold it in place during its reciprocating operating motion.